Low profile circuit breaker with self cleaning contacts

Abstract

A circuit interrupter includes a stationary contact and a moveable contact arm assembly having a moveable contact positioned thereon, the moveable contact configured to be moveable into and out of physical contact with the stationary contact. The circuit interrupter also includes an overcurrent tripping device coupled to the moveable contact arm assembly via a linkage assembly and configured to move the moveable contact out of physical contact with the stationary contact upon detection of an overcurrent situation. The moveable contact arm assembly is connected to the linkage assembly via at least two pivots positioned on the contact arm assembly, so as to cause a relative sliding action between the moveable and stationary contacts as the moveable and stationary contacts are moved into or out of contact with each other such that a wiping action is created in order to clean the moveable and stationary contacts.

Claims

1. A circuit interrupter having a housing within which components of the circuit interrupter are disposed, the circuit interrupter comprising: a line terminal connectable to a source of electrical power; a load terminal connectable to a load; a stationary contact positioned within said housing; a moveable contact arm assembly having a moveable contact positioned thereon, the moveable contact arm assembly comprising a contact arm carriage and a contact arm member, the contact arm member slideable within the contact arm carriage, the moveable contact configured to be moveable into and out of physical contact with the stationary contact by movement of the moveable contact arm assembly so as to place the line terminal and the load terminal into and out of electrical communication; and an overcurrent tripping device coupled to the moveable contact arm assembly via a linkage assembly and configured to move the moveable contact out of physical contact with the stationary contact upon detection of an overcurrent situation; wherein the moveable contact arm assembly is connected to the linkage assembly via at least two pivots positioned on the contact arm carriage of the contact arm assembly, so as to cause a relative sliding action between the moveable contact and the stationary contact as the moveable contact and the stationary contact are moved into or out of contact with each other such that a wiping action is created in order to clean the moveable and stationary contacts.

2. The circuit interrupter of claim 1, wherein the contact arm carriage has at least one slot formed therein, and wherein the contact arm member comprises at least one pin projecting from a surface thereof, the at least one pin cooperating with and slideable within the at least one slot.

3. The circuit interrupter of claim 2, wherein the at least one pin slides within the at least one slot as the moveable contact and the stationary contact are moved into and out of contact with each other.

4. The circuit interrupter of claim 2, further comprising a biasing member cooperating with the contact arm carriage and the contact arm member, the biasing member biasing the contact arm carriage and the contact arm member with respect to each other such that the at least one pin is biased toward a first end of the at least one slot.

5. The circuit interrupter of claim 4, wherein the at least one pin is moveable against the bias toward a second end of the at least one slot as the moveable contact and the stationary contact are moved into and out of contact with each other.

6. The circuit interrupter of claim 4 wherein the biasing member is a spring positioned between the contact arm carriage and the contact arm member.

7. The circuit interrupter of claim 6, wherein the spring is a leaf spring.

8. The circuit interrupter of claim 1, further comprising a resetting mechanism adapted to reset the circuit interrupter and move the moveable contact into physical contact with the stationary contact by movement of the moveable contact arm assembly, the resetting mechanism being connected to the linkage assembly via at least two pivots positioned on the resetting mechanism.

9. The circuit interrupter of claim 8, wherein the resetting mechanism comprises a handle having a portion thereof extending from the housing adapted to be actuated by a user.

10. The circuit interrupter of claim 8, wherein the resetting mechanism comprises a push button mechanism having a portion thereof extending from the housing adapted to be actuated by a user.

11. A circuit interrupter having a housing within which components of the circuit interrupter are disposed, the circuit interrupter comprising: a line terminal connectable to a source of electrical power; a load terminal connectable to a load; a stationary contact positioned within said housing; a moveable contact arm assembly having a moveable contact positioned thereon, the moveable contact configured to be moveable into and out of physical contact with the stationary contact by movement of the moveable contact arm assembly so as to place the line terminal and the load terminal into and out of electrical communication, the moveable contact arm assembly comprising a contact arm carriage and a contact arm member, the contact arm member slideable within the contact arm carriage, and wherein the at least two pivots positioned on the contact arm assembly are positioned on the contact arm carriage; an overcurrent tripping device coupled to the moveable contact arm assembly via a linkage assembly and configured to move the moveable contact out of physical contact with the stationary contact upon detection of an overcurrent situation; wherein the moveable contact arm assembly is connected to the linkage assembly via at least two pivots positioned on the contact arm assembly, so as to cause a relative sliding action between the moveable contact and the stationary contact as the moveable contact and the stationary contact are moved into or out of contact with each other such that a wiping action is created in order to clean the moveable and stationary contacts; and a resetting mechanism adapted to reset the circuit interrupter and move the moveable contact into physical contact with the stationary contact by movement of the moveable contact arm assembly, the resetting mechanism being connected to the linkage assembly via at least two pivots positioned on the resetting mechanism.

12. The circuit interrupter of claim 11, wherein the contact arm carriage has at least one slot formed therein, and wherein the contact arm member comprises at least one pin projecting from a surface thereof, the at least one pin cooperating with and slideable within the at least one slot.

13. The circuit interrupter of claim 12, wherein the at least one pin slides within the at least one slot as the moveable contact and the stationary contact are moved into and out of contact with each other.

14. The circuit interrupter of claim 12, further comprising a biasing member cooperating with the contact arm carriage and the contact arm member, the biasing member biasing the contact arm carriage and the contact arm member with respect to each other such that the at least one pin is biased toward a first end of the at least one slot.

15. The circuit interrupter of claim 14, wherein the at least one pin is moveable against the bias toward a second end of the at least one slot as the moveable contact and the stationary contact are moved into and out of contact with each other.

16. The circuit interrupter of claim 14 wherein the biasing member is a spring positioned between the contact arm carriage and the contact arm member.

17. The circuit interrupter of claim 16, wherein the spring is a leaf spring.

18. The circuit interrupter of claim 11, wherein the resetting mechanism comprises a handle having a portion thereof extending from the housing adapted to be actuated by a user.

19. The circuit interrupter of claim 11, wherein the resetting mechanism comprises a push button mechanism having a portion thereof extending from the housing adapted to be actuated by a user.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) FIG. 1 is an illustration of one aspect of the circuit interrupter according to the invention.

(2) FIG. 2 is a partial view similar to FIG. 1, showing optional alterations to the circuit interrupter shown therein.

(3) FIG. 3 is another partial view similar to FIG. 1, showing further optional alterations to the circuit interrupter shown therein.

(4) FIGS. 4A and 4B are illustrations of a portion of the circuit interrupter of FIGS. 1-3 showing the contacts in the open position and the closed position, respectively.

DETAILED DESCRIPTION OF THE INVENTION

(5) Referring now to the drawings, wherein like reference numerals designate corresponding structure throughout the views.

(6) FIG. 1 illustrates components of an example circuit interrupter 100 having an improved design that allows for a more compact circuit breaker and also for self-cleaning action of the contacts thereof according to aspects of the invention.

(7) Circuit interrupter 100 is provided with a housing 102 that contains the working elements of the device. The circuit interrupter is further provided with a set of contacts including a stationary contact 104 and movable contact 106. The moveable contact 106 is positioned on a moveable contact arm assembly 108, and the moveable contact 106 is configured to move between an open and closed position relative to the stationary contact 104. Reference to FIGS. 1-4A show the contacts 104, 106 in the open position where no electrical current flows therebetween; whereas FIG. 4B shows the contacts 104, 106 in a closed position.

(8) Also shown in FIG. 1 is a line terminal 110, which is designed to be connected to a source of electrical power, such as a bus bar in a panel board or load center. Stationary contact 104 is mounted onto a first conductive element 112, which in turn is electrically connected to line terminal 110 through an overcurrent tripping device 114.

(9) Moveable contact 106 mounted on moveable contact arm assembly 108 is in electrical communication with a load terminal 116 via a conductive connector 118.

(10) In operation, electrical power is input into circuit interrupter 100 via line terminal 110, which passes through overcurrent tripping device 114. If the electrical current exceeds a threshold level, overcurrent tripping device 114 will function to trip the circuit interrupter 100 by opening the circuit (opening the contacts relative to each other by means of a trip mechanism 120 and linkage assembly 122) such that the flow of electrical current through the contacts 104,106 ceases. In the event that the electrical current does not exceed the threshold level set by overcurrent tripping device 114, the electrical power is allowed to pass through load terminal 116, which in turn, provides electrical power to the connected circuit and/or equipment.

(11) The moveable contact arm assembly 108 is connected to the linkage assembly 122 via at least two pivots 124,126 positioned on the contact arm assembly 108. The pivots are arranged so as to cause a relative sliding action between the moveable contact 106 and the stationary contact 104 as the moveable contact 106 and the stationary contact 104 are moved into or out of contact with each other such that a wiping action is created in order to clean the moveable and stationary contacts 104,106.

(12) The circuit interrupter 110 also includes a resetting mechanism 128 adapted to reset the circuit interrupter 100 and move the moveable contact 106 into physical contact with the stationary contact 104 by movement of the moveable contact arm assembly 108. The resetting mechanism 128 is connected to the linkage assembly 122 via at least two pivots 130,132 positioned on the resetting mechanism 128, and has a portion extending from the housing adapted to be actuated by a user in order to reset the circuit interrupter 100 when it has been tripped. The resetting mechanism 128 may also be used to manually open the contacts 104,106, as is known in the art.

(13) In FIG. 1, the resetting mechanism 128 takes the form of a push-button that may be pressed by a user to reset a tripped circuit interrupter. In FIGS. 2 and 3, the resetting mechanism 128, 128 takes the form of a handle that may be pivoted by a user to reset a tripped circuit interrupter.

(14) With respect to FIG. 2, as compared to FIG. 1, another difference is that the line terminal 110 has been repositioned to be on the right side (with reference to the Figures) instead of on the left, as is the line terminal 110 shown in FIG. 1. Other similar changes may also be made without departing from the inventive aspects described herein.

(15) With respect to FIG. 3, as compared to FIG. 1, both the line terminal 110 and the load terminal 116 have been repositioned to face upward (with reference to the Figures), and the handle 128 has also repositioned to extend from the top surface of the housing 102. The position of the contacts 104,106 and the orientation of various other components, including the moveable contact arm assembly 108 have also been changed to accommodate the change in position of the terminals 110,116 and the handle 128, although the circuit interrupter 100 still functions in the same way as does the circuit interrupter 100 shown in FIG. 1 in pertinent respects. Circuit interrupter 100 of FIG. 3 is configured specifically to accommodate DIN rail mounting.

(16) Turning now specifically to FIGS. 4A and 4B, the moveable contact arm assembly 108, 108 includes a contact arm carriage 400 and a contact arm member 402, the contact arm member 402 slideable within the contact arm carriage 400. As can be seen, the aforementioned pivots 124,126 positioned on the contact arm assembly 108, 108 are more specifically positioned on the contact arm carriage 400. It is worth noting that although FIGS. 4A and 4B specifically show the orientation of components shown in FIG. 3, the configuration of the contact arm assembly 108, 108 is substantially the same in all of FIGS. 1-3, as described below.

(17) The contact arm carriage 400 has a slot 404 formed therein, the contact arm member 402 includes a pin 406 projecting from a surface thereof, the pin 406 cooperating with and slideable within the slot 404. This allows for a retained sliding and pivoting arrangement between the contact arm member 402 within the contact arm carriage 400, as will be understood by those skilled in the art.

(18) More specifically, the pin 406 slides within the slot 404 as the moveable contact 106 and the stationary contact 104 are moved into and out of contact with each other, which helps contribute to the relative wiping action therebetween.

(19) A biasing member 408 cooperates with the contact arm carriage 400 and the contact arm member 402, the biasing member 408 biasing the contact arm carriage 400 and the contact arm member 402 with respect to each other such that the pin 406 is biased toward a first end of the slot 404 (as shown in FIG. 4A). The pin 406 is moveable against the bias toward a second end of the slot 404 as the moveable contact 106 and the stationary contact 104 are moved into and out of contact with each other (as shown in FIG. 4B).

(20) The biasing member 408 may take the form of a spring positioned between the contact arm carriage 400 and the contact arm member 402, although it may take other forms as well. Even more specifically, in the embodiment shown in the Figures, the biasing member 408 takes the form of a leaf spring.

(21) Although the invention has been described with reference to a particular arrangement of parts, features and the like, these are not intended to exhaust all possible arrangements or features, and indeed many other modifications and variations will be ascertainable to those of skill in the art.